A simple method for transmission lines quality control

摘要

Transmission lines take a crucial role in verifying measurement accuracy of a calibrated vector network analyzer (VNA) as well as in establishing traceability of measured Sparameters. Difficulties in manufacturing of long transmission lines demand verification of the test transmission line before use. This work presents a simple method for comparing characteristic impedance of a test line with the reference. Accuracy improvement over the conventional method is achieved by the differential approach and data processing in the time domain. The proposed method was verified for coaxial lines manufactured by two vendors as well as for coplanar waveguide lines from NIST reference material RM8130 up to 70 GHz.